This has been going on a while...just haven't remembered to ask about it until now.
Car is a '10 with 40K mi. Always used full synthetic - last two oil changes have moved to 0w-20. Engine not modified or abused in any way. Runs great, great fuel mileage. No indications of ANY sort of problems.

The noise:
Best way to describe it is if someone was inside the engine compartment with a rattle-can of spray paint and shaking it vigorously. You know that sound, right?
But...this sound only seems to occur at low speeds/low RPMs...or when I engage the clutch and the RPMs are falling. I don't hear the sound when the car is stopped and idling. I also don't hear it if I'm accelerating...not even very light acceleration at low speed.
I always notice it when driving very slowly through the neighborhood in 2nd/3rd gear (around 25mph) and holding the gas peddle steady (NOT accelerating) or when coming to a stop and the RPMs are falling.

Anyone else recognize this? Is this a normal engine sound?

 

Perhaps the timing chain slapping.
It is difficult to judge without hearing the engine.
Here in Italy, Honda dealers don't advice oils 0w20, they are too thin. I have never been able to understand why and i don't believe it is just a fuel saving issue.

 

Did you have the noise before switching to 0w/20 oil? If it changed with the oil I would go back to whatever oil you were using.


Clifton

 

Been wondering the same thing...all I can recall is that it's been doing this for a LONG LONG time.

As a test, I'm going to try using 5w-30 (or is it 5w-20?) next time and see if it makes any difference.

Mainly just wanted to see if anyone else out there noticed their engines making a similar sound.

 

We had a rattle at low speed, coming from under the hood...turned out it was the hood support rod. Tie some tape to it and check if the noise is still present.

That was our situation too.

 

Yea...definitely not the hood rod though.

 

That could be sound of worn motor mount(support) which normally make rattling sound at very low speed or just start moving from stop. But I'm not sure if the symptoms are the same as I had

 

No, I'm 99.9% certain that it's valvetrain clatter. Just not sure if it's normal or not. When I do the next oil change and switch back to 5W-20, I'll see if that has an affect. If it doesn't I'm not sure how to record the noise for others to hear.
The noise level of what I'm hearing is low enough that I'm fairly certain that an audio recording wouldn't pick it up, from inside the cabin. Possibly if I rigged up something to record from inside the engine bay....

 

For the oil.... suck out with a large syringe (with a long tube ), say 1litre and replace with 1 litre of 10w30 and see if the noise reduces in the next 5 minutes of driving. 1 litre would be about ¼ of the total oil capacity and would make a sound difference if the 0w was the issue.

 

I logged in to search for this very issue.

You described the noise my car is making perfectly. I'm 100% certain we have the same noise. I just bought the car a few months ago and it's only got 32k miles. Have you determined the cause of this noise?

Is it something to worry about?

 

Nope. Still have the noise. Hasn't gotten any better or worse.
I'm pretty sure it's benign, but would still feel better if I was able to confirm that a lot of others hear the same noise and that it's just a Fit engine character trait.

 

I think lots of people have the noise, they just never drive slow enough with the radio off to hear it. I'm going to have the mechanic look at it soon. I'll let you know what he says.

 

Yea, if you do have someone check it out...I'd LOVE to hear what the professional analysis is!

 

Took the car in for an oil change at the dealer because it was free. Asked them to listen to it. The "lead service tech" didn't hear a thing. Of course.

They must have listened to it after they did the oil change because I couldn't hear it either on the way home. I guess the oil change fixed it. My guess is the "fix" is very temporary.

He did say that the car had the 09 lost motion spring recall done.

So, really no new info on this except that an oil change probably temporarily fixed it.

 

I believe I have the same noise on my '09 Sport MT. Something between the paint-can rattle you describe and a loose heat shield. Mine happens at around 2200 rpm, and seems to be worse when the engine is cold.

The thing is that mine wasn't there for the first 5.5 years, 130k miles. It seems to have developed this noise only in the past 4 months. Odd. I'll definitely post if I figure it out.

 

I got this noise too on my 2009 MT. It almost sounds like pre-ignition. I hope not because it happens at moderate loads. Would really feel better if I knew exactly whats causing it. I'm a bit past 100k miles (almost 170,000km), will get the valve lash checked soon, hopefully that clears it up. Doesn't really sounds like valve clatter to me though. More like a cracked exhaust manifold or some sort of high pressure exhaust leak.

 

Just an update... I changed my plugs tonight. Found the 3rd plug from the left when looking at the engine was very loose. I suspect the noise was exhaust leaking around the plug. Will know tomorrow with a test drive. The coil was all black with soot and the plug was discolored compared to the other three.

My VW tiguan had a loose plug at 60k miles too, so I will be checking any vehicle at 40k or earlier from now on. Don't trust these 100k service intervals. Too long for a small problem to turn into a more expensive one.

 

Thanks for the update. Please do let us know if the noise goes away with the tightened plug. I had my plugs replaced at the dealership in February and the noise started in April or May.

I've listened more carefully. It's definitely worse with the engine cold or even coldish--the noise continues after the blue light goes off but is gone after about 10 minutes of operation. It's also definitely at about 2200 rpm only, regardless of engine load, so I hear it as I accelerate through this region and then again with the clutch in as the revs drop across the 2200 region.

 

Well it runs great with the new plugs. But the noise is still there and it's exactly as you describe it. I wonder if it's the bearing on the input shaft to the transmission, my 1998 civic made a similar noise and that's what the culprit was.

I'm going to adjust the valves as part of the 100k mile maintenance soon. And have a look at all the heat shields.

 

I also found a loose clamp between the plastic intake and throttle body. It wasn't even close to tight.